Professor Albert H. Munsell (1858-1918) Author of A Color Notation and the Atlas of the Munsell Color System.
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The Reconstruction of the Portrait of Albert H. Munsell
The Munsell Color Science Laboratory (MCSL), located in the Center for Imaging
Science at the Rochester Institute of Technology, is the premier facility
in the United States for the study of Color Science. The laboratory's name
reflects it's lineage back to Professor Albert H. Munsell, the originator
of the Munsell Color Order System. Unfortunately, the MCSL did not have
a quality portrait of A.H. Munsell to hang in the laboratory to remind students,
faculty, and guests of the good professor and the lab's heritage. A project
was begun to remedy that deficiency.
The only known picture of A.H. Munsell was in the various editions of his
book, A Color Notation. While this picture was of moderate quality, a search
was made to find a better original to copy. The halftoned photograph in
the book was likely to have been initially shot on large format film (8X10
or larger) and would have, undoubtedly, been gorgeous by photographic standards.
After many phone calls and letters to such places as the Munsell division
of GretagMacbeth, no original photographs could be located. There was a
story of portraits hanging on the walls of the Baltimore office of the Munsell
division of GretagMacbeth but it was closed around 1990 and that lead was
a dead end as well.
With the limited resources available for the project, it was finally conceded
that the picture in A Color Notation would have to suffice. A generally
better reproduction of Munsell appeared in book editions of 1971 and prior.
The 1988 edition of the book had a picture which had been more tightly cropped
but, unfortunately, had highlights which were lacking tonal separation.
It did have smoother, less mottled midtones and shadows, however, than the
earlier editions. It was apparent that a new plate had been made for the
1988 edition. The printer might have had an original portrait on file but
we were unable to follow this potential lead. Ultimately, the picture of
A.H. Munsell in the earlier editions of his book was the one chosen for
reconstruction.
The picture in A Color Notation is about 4 1/4 X 5 5/8 inches in size and
was measured as being screened at 133 lines per inch with a traditional
round dot halftone screen. At this point the decision to use optical or
digital methods had to be made. Some pilot experiments indicated that it
might be possible to get better results removing the halftone screen digitally
rather than with conventional photographic copying with a slight, intentional
defocus to blur the screen. The screened book photo was scanned on a Hewlett-Packard
4c scanner at a non-interpolated 600 pixels per inch in gray scale mode.
In gray scale mode, the scanner collects 10 bits of intensity information
and outputs a file with "best" 8 bits from the data collected (probably
simulating something close to a lightness function).
Since the HP 4c scanner does not include descreening software, several alternate
methods were investigated to remove the halftone screen from the scanned
photo. In the human visual system, the screen drops below the visibility
limit when it is no longer resolved (is blurred). Pixel averaging, a type
of blurring or low pass filtering, over the scanned image was somewhat successful
but did not remove quite all screen frequencies, even at the optimum averaging
radius of 6 pixels. No commercial packages were found that could descreen
in the Fourier domain with a selective "notch" filter for the screen frequency.
Time did not permit writing an original computer program to do this. Also,
past experience has shown that sharp cutting "notch" filters of this type
sometimes produce other, undesirable, image artifacts. Some alternate scanning
software was purchased for its descreening function but this did a poorer
job than straight pixel averaging. Finally, an inexpensive software package
called ScanLikePro was purchased which produced superior results. This software
plugs into Adobe Photoshop's actions menu. It utilizes a proprietary ratio
of Photoshop's gaussian blur (which does most of the job) and image size
reduction (removes any residual screen frequency).
The tone scale of the image was expanded to fill the 8 bit digital count
range and the "gamma" was increased slightly to obtain better tonal separation
in the shadows at the expense of a little separation in the highlights.
It was hoped that some image sharpening could be applied at this point.
However, much of the Munsell image included dark areas. Even though reproduced
on glossy paper in the book, there was significant image noise, apparently
introduced by nonuniform ink-paper fiber interactions. This image noise
precluded sharpening since it was increased whenever Photoshop's unsharp
masking was invoked, regardless of frequency (pixel radius).
At this point, the image was taken to an Eastman Kodak facility to be printed.
D. Mark Reiman, another MCSL graduate student and Kodak employee, did the
final image processing in preparation for printing. First, the image size
was interpolated up to fit the width of the picture frame and was cropped
slightly to remove the foreground clutter. Most of Munsell's arm reflection
in the shiny table top was saved but the lower out-of-focus areas were removed
for better composition. Several major white dust spots were removed at this
time as well. The tone scale was modified to best fit the dynamic range
of the output device, a Kodak PS8650 thermal dye sublimation printer.
The first print was quite good but the overall "halated look" of the photo
was a bit too apparent. The picture in the book shows the effect. It is
probably due to the fact that most films around 1918 had little or no antihalation
protection. The image was darkened slightly which reduced the halation effect
but didn't affect the highlight brilliance too severely. The slightly darker
print also helped to mask another defect. The lack of shadow detail, which
was present in the book reproduction, looks odd in Munsell's silver hair.
The slightly darker print helped this area blend more naturally into the
dark backdrop in the scene. The final print was output at 300 d.p.i. on
Kodak Ektatherm CMY media with a protective overcoat (laminate) layer at
8 1/2 inches wide (2550 pixels) by 9 1/4 inches in height (2761 pixels).
This represents about a 2X enlargement over the book's reproduction. It
is about the maximum size which looks acceptably sharp without using image
sharpening algorithms.
The print was framed and now hangs in the main laboratory room of the MCSL.
It also includes the following brief inscription:
Professor Albert H. Munsell -- Born in Boston, Massachusetts
on January 6th, 1858 and died June 28th, 1918 at age 60, he was the author
of A Color Notation (1905) and the Atlas of the Munsell Color Order System
(1915). Both an artist of distinction and gifted teacher of art, he developed
the first widely-accepted color order system to make the description of
color accurate and convenient and to aid in the teaching of color. The
Munsell color order system has gained international acceptance and has
served as the basis for other color order systems. -- Albert Munsell founded
the Munsell Color Company in 1917. Later, in 1942 The Munsell Color Foundation
was formed by the company to promote the advancement of the science of
color. Ultimately, the Munsell Color Foundation led to the founding of
this laboratory, the Munsell Color Science Laboratory, in 1983, at the
Rochester Institute of Technology.
The framed portrait of Albert H. Munsell looks quite good considering
the limited resources available for the reconstruction work. If time permits
in the future, some advanced image processing could yield an even better
result. In particular, tone-scale-related image sharpening could be of
value. The shadow areas which show the most image noise could be low-pass
filtered (blurred) slightly to reduce the effect while the highlight areas
could be sharpened since they are relatively noise free. Also, it may
be possible to combine the best parts of the Munsell images from the different
editions of A Color Notation. The highlights and midtones from the earlier
edition could be combined with the shadow areas of the newest edition.
Ultimately, if a first generation photographic original becomes available,
it would solve most of these problems. Please contact the MCSL if you
know of one.
It would be desirable to show the reconstructed portrait of Albert H.
Munsell here on the pages of COLOR Research and Application. However,
due to space constraints, it would have to be reduced in size and would
have to be rescreened in the graphic arts process. As a better alternative,
a jpeg-compressed copy is being placed on the Internet website of the
MCSL. In this form, it does not need to be screened. View the image using
the appropriate link below. A special note of thanks is due Cal McCamy
for loaning his 1971 edition of A Color Notation for the project.
Douglas Corbin
Former Graduate Student, Munsell Color Science Laboratory
There are three images available:
Image corrected for typical
PC/Windows monitor
Image corrected for typical
Macintosh monitor
Uncorrected image(large image - 21MB!)
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